As a point of educational order, you can't have a core activity for some pupils. Core means all the kids do it.
I hate publicly-funded religious schools: they're at the heart of what's wrong with academies and free schools (even though these schools aren't). What has been said about the goings on at these schools makes me want to close those schools tomorrow BUT, but-but-BUT... it's no worse really than goes on at some Jewish and Catholic schools, and they aren't being put into special measures - far from it. Gove fucking praised Catholic schools to the rafters in an article published today. Invited them to become academies *because* it would give them more freedom to do things their way, change the curriculum etc. Just like these Islamic schools have been doing.
This isn't about educational values, ffs - this is cheap islamaphobia.